I did look at that animation a week or so ago. Someone on the tech forum was asking about it. From what I can tell in the short amount of time I spent looking at it. It looks like the hip needs to be repositioned first. Then the rthigh,rshin,rfoot after that. The hip seems to be too high when the right leg is extended in the forward direction. Causing what's known as Gimbal lock (knee locks). I'm afraid only a complete re-write of the keyframes can fix it properly. But I'm no expert on that sort of thing. I've never really messed with it much. ScottA